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arXiv · 1801.03156

Asymmetric information capacities of reciprocal pairs of quantum channels

Matteo Rosati·Vittorio Giovannetti
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Abstract

Reciprocal pairs of quantum channels are defined as completely positive transformations which admit a rigid, distance-preserving, yet not completely-positive transformation that allows to reproduce the outcome of one from the corresponding outcome of the other. From a classical perspective these transmission lines should exhibit the same communication efficiency. This is no longer the case in the quantum setting: explicit asymmetric behaviours are reported studying the classical communication capacities of reciprocal pairs of depolarizing and Weyl-covariant channels.

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Matteo Rosati, Vittorio Giovannetti. 2018-01-09. Asymmetric information capacities of reciprocal pairs of quantum channels. https://doi.org/10.1103/physreva.97.052318

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